This application relates to an improved spring brake actuator wherein a dome extends into the service chamber from the center housing, and aligns the spring chamber push rod and the service chamber push rod.
Spring brake actuators are known wherein centering devices are provided between the push rod and the power spring. Known brake actuators have typically not included structure to align the push rod in the spring chamber with the push rod in the service chamber. If there is misalignment between the two push rods, then it becomes more difficult for the spring brake actuator to function properly.
Moreover, it is a goal of modem spring brake designers to minimize the required axial length of the spring brake actuator. It is additionally a goal of any design to minimize the amount of material required for the item. To this end, it would be desirable to minimize required axial length of the spring brake actuator design, and to minimize the material required for the housing members of the spring brake actuator. In the past, a dome has often extended from the center housing into the spring chamber. This dome provides guidance over sufficient length such that the spring chamber push rod is guided during movement by the center housing. The prior art dome extending into the spring chamber does not provided any guidance or alignment to the service chamber push rod or diaphragm.